Forklift trucks have been used either to lift goods of relatively heavy weight up to an elevated location or to lower the goods on the ground. The forklift trucks also can be used to move the goods from one place to another within a limited working area. Depending on the power sources employed, the forklift trucks are classified into an engine-driven forklift truck which may usually operate in an outdoor area and an electromotive forklift truck which are suitable for indoor operation, thanks to its reduced or little emission of exhaust gas and operating noise. The electromotive forklift truck is usually provided with an electric pump motor which in turn serves to rotatingly drive a fluid pump for discharging high pressure working fluid to be supplied to a steering system, a brake system and a variety of working implements.
With reference to FIGS. 1 and 2, there is illustrated a typical motor mounting structure wherein a pump motor 10 is detachably mounted to a frame 12 of a forklift truck. The pump motor 10 is adapted to be supplied with electricity from a rechargeable battery(not shown) and can produce torque needed to rotate a fluid pump 14 which remains directly coupled to the pump motor 10.
In the illustrated prior art example, the pump motor 10 is provided with a motor bracket 16 firmly secured at four points to the frame 12 by bolt-nut fastener units 18 in a suspended condition. Each of the bolt-nut fastener units 18 consists of a bolt 20 passing through the thickness of the frame 12 and the motor bracket 16, a couple of washers 22, a bushing 24 and a nut 26 threadedly coupled to the bolt 20.
One drawback of the above-mentioned prior art motor mounting structure is that, in order to attach or detach the pump motor to or from the forklift trucker frame, all of the fastener units have to be completely tightened or untigthened through the use of a suitable wrench not shown in the drawings. This would make the task of mounting or demounting the pump motor time-consuming and laborious. The narrow spacing left between the pump motor and the motor bracket makes it difficult to gain access to and then turn the nut with a wrench.
The prior art mounting structure as set forth above is also disadvantageous in that it has a single fixed mounting position and therefore cannot be shifted to a temporary maintenance position wherein parts or components of the pump motor may be readily checked, repaired and replaced with little possibility of interference with environmental structures. This means that complete removal of the pump motor from the vehicle frame is unavoidable whenever needs exist for maintenance of the motor components, however trivial the nature of maintenance may be. Attendant problems in the complete removable of the pump motor is that fluid lines and/or electrical harness must be disconnected and reconnected before and after the pump motor removal operation. In addition to the above shortcomings, the prior art pump motor mounting structure is unsuitable for effectively inhibiting vibration of the pump motor from delivery to the vehicle frame, which would hinder comfortable driving of the industrial vehicle.